Crank-case construction for gas-engines.



J. T. MOLTRUP.

CRANK CASE GONSTRUGTION FOR GAS ENGINES APPLICATION FILED APILM. 1908.

993,863. Patented May 30, 1911.

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J. T. MOLTRUP.

CRANK CASE CONSTRUCTION FOB. GAS'BNGINES.

APPLIQATION TILED 33.24. 1908.

Patented May 30, 1911.

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JAMES T. MOLTRUP, OF BEAVER FALLS, PENNSYLVANIA.

CRANK-CASE CONSTRUCTION FOR GAS-ENGINES.

Specification of Letters Patent.

Application filed April 24, 1908.

Patented May 30, 1911.

Serial No. 428,942.

To all whom it may concern:

Be it known that I, JAMES T. MOLTRUP, of Beaver Falls, county of Beaver,and State of Pennsylvania, have invented a new and useful Im rovement inCrank-Case Constructions for as-Engines, of which the following is afull, clear, and exact description, reference being had to theaccompanying drawings, forming part of this specification, in whichFigure 1 is a vertical section of a gas engine embodying my invention;Fig. 2 is a side view of the same, partly in section and partly brokenaway, with the cam shaft removed; Figs. 3 and 4 are respectively planand end elevations of the upper portion of one of the crank case headsdetached, and with the side-supporting lugs removed; and Fig. 5 is adetail view of the intermediate hangers or bearings on a smaller scale.

My invention has relation to a crank case construction for gas engines,and is designed to provide a crank case which shall be simple in itsconstruction and strong and light.

The precise nature of my invention will be best understood by referenceto the accompanying drawings, in which I have shown one embodimentthereof, it being premised, however, that various changes may be madetherein by those skilled in the art, without departing from the spiritand scope of my invention, as defined in the appended claims.

In the drawings, the numeral 2 designates the cylinders of a multiplecylinder gas engine. 8 designates one of the pistons; 4 the pitman whichconnects it with the crank 5 of the crank shaft 6, which is common toall the cylinders; 7 the inlet valve for said cylinder, and 8 the outletvalve. 9 and 10 designate the connections for operating said valves,which connections are operated by cam shafts 11, which extend throughthe crank case. These parts may be of any suitable character, as myinvention relates solely to the construction of the crank case and tothe manner of supporting the cylinders thereon.

My improved crank case consists of heads 12, preferably castings of theform best shown in Figs. 3 and 4. Each of these heads has an extendeddivided bearing 13, for the crank shaft and is formed with an inwardlyprojecting flange portion 14, cut away at 15 for the end cylinder. Theseheads and bearings are preferably reinforced by the webs 16. The portionof each head below the divided bearing may be and preferably is,composed of a separate piece of lighter metal, as clearly shown in Fig.2. Each head also contains bearings 17, for the cam shafts 11. Rivetedor otherwise firmly secured to the flange portions 14 of the heads andconnecting the same is a sheet metal casing 18, which is preferablyformedin two sections united by the bolted flange 18. Each head is alsoprovided with laterally. projecting shouldered lugs 19, by means ofwhich the crank case is supported on the engine frame (not shown). Theselugs are shown as being secured by riveting to the heads and theirflanges 14 through the casing. Intermediate the two heads is a hanger orbracket 20, which has bearings 21, for the cam shafts 11 and also abearing 22 for the crank shaft. This hanger is bolted or otherwisesecured to the metal casing 18, as shown at 23, in

Fig. 2. This hanger is shown as being of 1 I-beam form in cross section,its upper flanges being extended laterally underneath a portion of theadjacent cylinder seats. The bearings 21 are preferably split, asindicated in Fig. 5, and the bearing 22 has a removable cap section 22*.

The upper section of the metal casing 18, preferably has its flat topportion of greater thickness than its side portions, the rolling flanges18 being also of greater thickness than the side portions. This enablesthe thicker portions to be machined for proper fitting without undulythinning them, and gives greater strength where most needed, withoutincreasing the weight of the side portions.

It will be seen that the end cylinders are supported on the flangeportions 14 of the two heads, while the intermediate cylinders aresupported largely on the hanger or bracket 20, thus relieving the metalcasin l8 largely of the weight of the cylinders an enabling such casingto be made of relatively thin light sheet metal.

The heads of the crank case bein in the form of castings can be madesufliciently strong to provide the main bearings for the crank shaft andto carry the weight of the cylinders.

The construction is as a whole very simple and strong and can be readilyassembled. I do not, however, limit myself to the exact form ofconstruction which I have shown and described, since various changes maybe made therein without departing from the spirit and scopeof myinvention Thus, the form of the end heads and of the intermediatebracket or hanger may be changed, and one or more of the intermediatehangers may be provided, according to the length of the crank case.

I claim:

1. In a gas engine, a crank shaft, a plurality of cylinders having theirpistons con nected to said shaft, and a crank casing, said casingcomprising separate rigid heads having bearings for the crank shaft, anda sheet metal casing secured to said heads and provided with seats forthe cylinders, said heads having inwardly projecting longitudinalflanges to which the sheet metal casing is secured, said flanges beingextended underneath the adjacent cylinder seats of the sheet metalcasing; substantially as described.

2. In a gas engine, a crank shaft, a plurality of cylinders having theirpistons connected to said shaft, and a crank case, said case comprisingseparate rigid heads carrying end bearings for the crank shaft, a sheetmetal casing, lateral supports for said casing secured to said heads,the upper portion of the sheet metal casing being provided with seatsfor the cylinders, and the heads having inward projections extendingunderneath the adjacent cylinder seats to thereby sup port the same;substantially as described.

3. In a gas engine, a crank shaft, a plurality of cylinders having theirpistons connected to said shaft, and a crank case, said case comprisingseparate rigid heads carrying end bearings for the crank shaft, a sheetmetal casing, lateral supports for the casing secured to said heads, theupper portion of the sheet metal casing being provided with seats forthe cylinders, and the heads having inward projections extendingunderneath the adjacent cylinder getter-.6 thereby support the same, thesheet metal casing also having an intermediate bracket or hanger securedto and suspended from its upper portion, said bracket or hanger having abearing for the crank shaft and also having flanges which extendunderneath the ad jacent cylinder seats at each side of the bracket orhanger; substantially as described.

41:. In a gas engine, a crank shaft, a plural- 4 ity of cylinders havingtheir pistons connected to said shaft, and a crank casing, said casingcomprising separate rigid heads having bearings for the crank shaft, anda sheet metal casing secured to said heads and provided with seats forthe cylinders, said heads having. inwardly projecting longitudinalflanges to which the sheet metal casing is secured, said flanges beingextended underneath the adjacent cylinder seats of the sheet metalcasing, and lateral supporting lugs for said casing which are secured tothe flanges of the heads; substantially as described.

5. In agas engine, a crank case head, comprising a casting provided witha divided bearing for the crank shaft, said casting also having aninturned riveting flange and a horizontal flange at its upper portionwhich extends inwardly to form a cylinder support, together with a sheetmetal case body overlying said horizontal flange and secured thereto andalso to the inturned riveting flange of the head, substantially asdescribed.

In testimony whereof, I have hereunto set H. M. CoRWIN, GEORGE H.PARMELEE.

Gopies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C.

